From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.5 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 33411C04A6B for ; Mon, 6 May 2019 10:37:13 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id F1C5520830 for ; Mon, 6 May 2019 10:37:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=web.de header.i=@web.de header.b="d228zJ7/" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F1C5520830 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=web.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([127.0.0.1]:54146 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hNazg-0001PS-77 for qemu-devel@archiver.kernel.org; Mon, 06 May 2019 06:37:12 -0400 Received: from eggs.gnu.org ([209.51.188.92]:53631) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hNayg-0000w8-Cq for qemu-devel@nongnu.org; Mon, 06 May 2019 06:36:11 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hNayf-0008BT-2L for qemu-devel@nongnu.org; Mon, 06 May 2019 06:36:10 -0400 Received: from mout.web.de ([212.227.17.12]:52753) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1hNaye-0008AQ-6T for qemu-devel@nongnu.org; Mon, 06 May 2019 06:36:08 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=web.de; s=dbaedf251592; t=1557138947; bh=4j8FL9g6gVrZ+bFrk1QDPPWCE2RP5egzfvDj/PhUNOA=; h=X-UI-Sender-Class:Date:From:To:Cc:Subject:In-Reply-To:References; b=d228zJ7/IcdgO5xP/Rsea+GfWztYlSfEtvMHgeD8NMch7JTtj3YISUOmE32cnQUgX Q/0f4nQX66tPQtcPmwBUxvl5oyNhG03+awJAbPY0lzwJ8NnyqESKPiiOZPKC0/u38T 0UUiJ9JKB5WUj00RFgJ4x0dMFgAYNDF4+7ye/ThY= X-UI-Sender-Class: c548c8c5-30a9-4db5-a2e7-cb6cb037b8f9 Received: from luklap ([2.247.244.216]) by smtp.web.de (mrweb102 [213.165.67.124]) with ESMTPSA (Nemesis) id 0LfAsW-1gvB7b1xSC-00oldJ; Mon, 06 May 2019 12:35:47 +0200 Date: Mon, 6 May 2019 12:32:58 +0200 From: Lukas Straub To: qemu-devel@nongnu.org Message-ID: <20190506123020.23d168a3@luklap> In-Reply-To: <20190420191425.7d1dab82@luklap> References: <20190420191425.7d1dab82@luklap> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable X-Provags-ID: V03:K1:jJ7J1bz3oXyb0T7rWBo+Bx4A/RRblLGlMQWI+iZ4Hxa9bf2pZbO eOHnQLzenNt4TLjN9D2RtZmkluE4dncEsv+qcyMnDTWafYey978fLWXXb3L25BNTnN2bbrU 4aNAeXXXZYD6yRaQnk9jq2Ibz2cFZ4KFI49zIZaEKDn0ejJajFRelnTLEP4yDW6rJ14pSSZ HpVRYl4DpnzQrTvJNgzJA== X-UI-Out-Filterresults: notjunk:1;V03:K0:afxIkHm0k0s=:IEW7apg4qf3rXm4JZ1e9L3 vUVLM3UjZmn/RybZ3GonKqbkvnnLM/XkO5nvRmILA8RRpXjwffvGhccMlx1jKGUBoqDSmP12k I+DyoYerwKkO4rb6qsBZ5h4qBeJbHqroUHz+EcfGSFA0nJYnSU/hZ6nU0ZXlHMed6fuK6MEGG HGdunWuGT7vn/NZF3jvtCWlN0ri6tq8QUppl0ZIiO30hRmqr6bk3XSxg/cvaUFC4zc+Uta/tm JJMUBbr57aORSPBL4aYhvg4nEWyux/S8y3IYLCQtE/U/zrFFW3u7uZ1arpOs5omZM6x/zm2sg pmcMvKZPq/oYkumvxiZKzh5LCtN0Ca7oQ4y0h3kNukmvd8nGspza8jPmDSdUMli/HMIDEDYor YLhsJvcPAkp5biAqVTcHwoAj6b6xpujYlJtZfH2Lu2rni4lJvKWidbEjBmEMrWANFh13K+Y01 N8LH/DBOeLtt+sQHpvFGIydHuCvnkSMjHqH+ws6iHA1/kyMUOoCQXtmBpWKvRhMfAPmX+PIMe mAk27/MdGbuSReHW5pOcNb871QV5knLWHBhic9ixYBm3V0q3T1raPyrahBykVoet8mGUVWOvQ B/vEFWsqSesVArO0IqP1g9RqLvEyFxG1KdmaouRuIXKqCN0UCL/9MMyrXO/hKXve/pHkaAmuj gocSUH+q6MmV1Lm7e9VjI7jsZfYLmfP6LqjH2ZWHsZFXEXfTlXesqpdNZXVPn4EYsjNJYhCw2 jzN6B87tciaJBKyPBaimie1Lm84T0w5vMyl4WM7k+XNdh2K5+JpuV6JZlJrGSDHL/IqQUqIbw XmDm2ZQAUdIP6p/9yNwNS7Aze/odfBVM8l89RawHyqTQEcsdgvk8zF+t4qMlvPB/x8/OmtHCh FNPFdLHY2HjSX19N6fu67ZxptLEIuQn/uUhY+Yx1aNh+iWTLuY20n2blqURxBJwyRdCudYcl5 WVHDIwODWTg== X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 212.227.17.12 Subject: Re: [Qemu-devel] [PATCH v2] net/colo-compare.c: Fix a crash in COLO Primary. X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: "Zhang, Chen" , Jason Wang Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Sat, 20 Apr 2019 19:14:25 +0200 Lukas Straub wrote: > From: Lukas Straub > Because event_unhandled_count may be accessed concurrently, it needs > to be protected by taking the lock. However the assert is outside the > lock, probably causing it to read garbage and aborting Qemu > erroneously. > > The Bug only happens when running Qemu in COLO mode. > > This Patch fixes the following bug: > https://bugs.launchpad.net/qemu/+bug/1824622 > > Signed-off-by: Lukas Straub > --- > net/colo-compare.c | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > > diff --git a/net/colo-compare.c b/net/colo-compare.c > index bf10526f05..fcb491121b 100644 > --- a/net/colo-compare.c > +++ b/net/colo-compare.c > @@ -813,9 +813,8 @@ static void colo_compare_handle_event(void > *opaque) break; > } > > - assert(event_unhandled_count > 0); > - > qemu_mutex_lock(&event_mtx); > + assert(event_unhandled_count > 0); > event_unhandled_count--; > qemu_cond_broadcast(&event_complete_cond); > qemu_mutex_unlock(&event_mtx); Ping. Regards, Lukas Straub